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big injectors - problems

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Old 02-20-2006, 02:12 PM
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Default big injectors - problems

Are there any disadvantages with big injectors...

I´m changing my stocks for #50
Old 02-20-2006, 04:08 PM
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No reason to if you don't have any mods that require more fuel.

Will not gain any power from larger injectors, put the money towards a power making mod.
Old 02-20-2006, 10:17 PM
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Yes i know....

Thats not what i was asking.
Old 02-21-2006, 09:24 PM
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If they are msd/holley 50 lb they will be a little bit of work to tune. You will have to adjust the injector flow rate table and the injector timing table (how fast the injectors open.

Gary
Old 02-23-2006, 12:56 PM
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OK... thanks for the answers.
Old 02-23-2006, 10:20 PM
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Im going to say that going with larger injectors is going to show some problems on the scans. I just dropped in 60lb injectors with no boost yet and the decels are causing major rich issues because the PCM cant command a low enough injector pulse width. To get around this I need to get a vacuum referenced fuel pressure regulator otherwise the rich decels are going to continue to happen which causes hesitation if I get on the gas during the rich decel.

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Old 02-23-2006, 11:44 PM
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50's ain't big...I just ditched a set of 83's for a set of 160's. If tuned properly, there shouldn't be any issues.
Old 02-24-2006, 08:32 AM
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Damn, how are you guys getting these big of injectors to work on NA engines? 60 is pushing it as far as the ECM can command on pulse width on decels and idle.

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Old 02-25-2006, 01:54 AM
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Originally Posted by Dixit
Damn, how are you guys getting these big of injectors to work on NA engines? 60 is pushing it as far as the ECM can command on pulse width on decels and idle.

Dixit
Not NA, but I don't see how that effects idle nor decel (off boost conditions). Use a boost/vac referenced return style regulator. And, if need be, back down the fuel pressure. IMO, the 58-60# constant fuel pressures come with a tradeoff...injectors flow more at higher pressures, but fuel pumps flow more at lower pressures. If you've got overkill on your injector sizing, back the pressure down...combined with the additional drop from the vac referenced regulator, it should be much easier to tune for better idle & decel qualities.




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